Re: [PATCHv2] arm: crypto: Add optimized SHA-256/224

[Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>]

On 15:46 Tue 24 Mar     , Ard Biesheuvel wrote:
> On 24 March 2015 at 14:06, Ard Biesheuvel <ard.biesheuvel@linaro.org> wrote:
> > On 24 March 2015 at 14:05, Jean-Christophe PLAGNIOL-VILLARD
> > <plagnioj@jcrosoft.com> wrote:
> >>  >> +     '&eor   ($t0,$t0,$a,"ror#".($Sigma0[2]-$Sigma0[0]))',   # Sigma0(a)
> >>> >> +     '&add   ($h,$h,$t1)',                   # h+=Ch(e,f,g)
> >>> >> +     '&ldr   ($t1,sprintf "[sp,#%d]",4*(($j+1)&15))  if (($j&15)!=15);'.
> >>> >> +     '&ldr   ($t1,"[$Ktbl]")                         if ($j==15);'.
> >>> >> +     '&ldr   ($t1,"[sp,#64]")                        if ($j==31)',
> >>> >> +     '&and   ($t3,$t3,$t2)',                 # (b^c)&=(a^b)
> >>> >> +     '&add   ($d,$d,$h)',                    # d+=h
> >>> >> +     '&add   ($h,$h,$t0,"ror#$Sigma0[0]");'. # h+=Sigma0(a)
> >>> >> +     '&eor   ($t3,$t3,$b)',                  # Maj(a,b,c)
> >>> >> +     '$j++;  unshift(@V,pop(@V)); ($t2,$t3)=($t3,$t2);'
> >>> >> +     )
> >>> >> +}
> >>> >> +
> >>> >> +$code.=<<___;
> >>> >> +#if __ARM_MAX_ARCH__>=7
> >>> > this will be compile on armv4 but gcc will not allow it
> >>> >
> >>> > we need to drop the neon code for older non v7 build
> >>> >
> >>>
> >>> The .arch and .fpu declarations ensure that it can be built regardless
> >>> of the platform you are compiling for, unless you have a really old
> >>> toolchain.
> >> I known but does not work for me
> >>> The glue code ensures that the module can only be loaded if HWCAP_NEON is set.
> >>>
> >>> Did you get errors trying to build it?
> >>
> >> yes I do
> >>
> >> I use
> >>
> >> arm-none-linux-gnueabi-gcc (Sourcery CodeBench Lite 2014.05-29) 4.8.3 20140320
> >> (prerelease)
> >> Copyright (C) 2013 Free Software Foundation, Inc.
> >> This is free software; see the source for copying conditions.  There is NO
> >> warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
> >>
> >> so it's not that old
> >>
> >
> > Could you share the error log please?
> 
> OK, I spotted one issue with this code:
> 
> arch/arm/crypto/sha256-core.S: Assembler messages:
> arch/arm/crypto/sha256-core.S:1847: Error: invalid constant (ffffefb0)
> after fixup

yes exactly
> 
> This is caused by the fact that, when building the integer-only code
> for an older architecture, the conditional compilation produces a
> slightly bigger preceding function, and the symbol K256 is out of
> range for the adr instruction.

Yeap I see that too when debuging
> 
> @Jean-Christophe: is that the same problem that you hit?
> 
> @Andy: I propose we do something similar as in the bsaes code:
> 
> #ifdef __thumb__
> #define adrl adr
> #endif
> 
> and replace the offending line with
> 
> adrl r14,K256

Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Tested-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>

on arm926ejs

Best Regards,
J.